Absorption of SO2 by Basic Oxygen Furnace Slag
Date Issued
2005
Date
2005
Author(s)
Sung, Wen-Fang
DOI
zh-TW
Abstract
Basic oxygen furnace slag (BOF slag), which contains about 40 wt.% CaO, is a waste in the steelmaking process. The feasibility of utilizing BOF slag for SO2 absorption was studied in this work. Ground BOF slag together with hydrated lime (HL), or recycled glass powder (FG3), or HCl solution were slurried and dried to obtain sorbents. The sorbents were reacted with SO2 in a differential fixed bed reactor under the conditions simulating the dry flue gas desulfurization (dry FGD) process (60℃, 70%RH, and 1000 ppm SO2) to measure their reactivities toward SO2 for sorbents were measured.
No hydration products with high specific surface area were produced during the process of slurrying BOF3 with HL (L/S=10/1). The sorbent specific surface areas (about 11-19 m2/g) was not closely correlated with BOF3/HL weight ratio (100/0-0/100), slurrying temperatures (25-95℃), and slurrying time (0.42-32 hr). However, calcium silica hydrates with high specific surface area were formed for BOF3/FG3 sorbents (50/50) during the slurrying process. Calcium content of BOF was partially converted to deliquescent CaCl2 by the addition of HCl. The one hour utilization of Ca for ground raw BOF3 was 0.14, lower than that of HL (0.19). The BOF3/HL sorbents had higher Ca utilization than HL when the weight ratio was smaller than 50/50, and the sorbent with a 40/60 ratio had the maximum value of 0.31. The sorbent with a 10/90 ratio had the maximum SO2 capture, 0.22 g SO2/g sorbent, which was slightly higher than that for the sorbent with a 40/60 ratio, 0.21 g SO2/g sorbent. The Ca utilization for the sorbents prepared by slurrying BOF3 with HCl solution at room temperature varied as the added amount of HCl changed, and reached a maximum value of 0.35 at 0.1 mol HCl/100g BOF3; the SO2 capture for this sorbent, 0.14 g SO2/g sorbent, however, was lower than the best SO2 capture for BOF3/HL sorbents.
Subjects
轉爐石
二氧化硫
吸收劑
煙道氣除硫法
鈣利用率
二氧化硫捕捉率
BOF
SO2
sorbent
FGD
Ca utilization
SC
Type
thesis